Abstract
OBJECTIVES: The purpose of this study was to apply the amplitude of the low-frequency fluctuation (ALFF) method to investigate the spontaneous brain activity alterations in patients with residual dizziness (RD) after successful canalith repositioning manoeuvre for benign paroxysmal positional vertigo (BPPV). METHODS: All BPPV patients underwent visual vertigo analog scale (VVAS) evaluations and functional magnetic resonance imaging (fMRI). The ALFF method was used to assess the spontaneous brain activity. Screening of brain regions with significant changes in ALFF values was based on analysis of the whole brain. We further analyze the relationship between ALFF values of the altered regions and VVAS scores in BPPV patients with RD. RESULTS: Fifteen BPPV patients with RD and fifteen without RD were recruited in this study. In contrast to without RD, RD patients exhibited increased scores in VVAS tests (p < 0.001) and RD patients also showed significant ALFF decrease in the bilateral precuneus (left: 251 voxels; x = -10, y = -69, z = 51; peak t-value = -3.25; right: 170 voxels; x = 4, y = -59, z = 42; peak t-value = -3.43). Correlation analysis revealed that the mean ALFF z-values in the left precuneus displayed significant negative correlations with the VVAS scores(r = -0.44, p = 0.01). CONCLUSIONS: This study shows that RD is associated with left precuneus function as revealed by fMRI. It might provide useful information for explaining neural mechanisms in BPPV patients with RD.